567 Victorian 4-4-0 New Build

Well there has been enough going on behind the scenes....so I do hope the next newsletter is very encouraging! We did look at the driving wheels in conjunction with the Churchward County Group, the big problem was the center boss detail of theirs was nearly twice as big as 567. So no, not driving wheel pattern. The CNC machine cut all this in 3 working days out of dense engineering plywood - We should have credited Dave at General Patterns Ltd with the pic.

 

I thought the radius looked too large for a bogie wheel boss (although knowing how canny photographers can be....). My thought was that it's the bogie bolster.

 

Keep thinking on - or await the newsletter/web post

 

Working on the design of the Vacuum Brake System, and now looking at a very small vital component to ensure things work correctly. I am contacting the vast web of Knowledge out there - requesting assistance.....

I was given a batch of SAR drawings that has a detail of a suitable Drip Trap - thatn however, unfortunately uses a 17/32" dia brass ball - which is non existent in UK , but is available in bulk from the USA. Our Chief Engineer has advised me that there is a Heritage supply that uses a synthetic rubber ball. Anyone got info on this assembly - we will need 3 or 4 for the system?

 

Could you not modify the design to take 1/2" or 15mm brass balls available here https://www.ballandrollerstore.com/brass-ball-bearings/ Have you considered 1/2" stainless balls? If you need to go slightly larger than 17/32" rather than smaller 14mm stainless ones are readily available in the UK in quantities as low as 1.
Ray.

 

Yes Ray, I had found these balls you kindly noted, but the concern that I have is the Drip Trap forms part of a Safety Critical System. The use of a proven assembly is accepted by the ORR & Insurers (we are not going Main Line), but our Technical Construction file must contain valid data as to the new or revised design. It is easier to track down this Heritage Component than going through proving tests for a modified design.

 

Wouldn't a rubber ball be just as much a "new or revised design"?

 

With all due respect, I think you need to get real on this. These things happen all the time and minor changes such as this have little consequence. I bet, if you bought a drip valve from south coast steam, they would modify to suit the available materials, whethwer it was going to stainless steel or the nearest metric equivalent.

the ORR will have no interest with this. The only person who might have a passing interest is your ICP and I'm sure that an e-mail to them would result in a letter of no objection.

 

Alternatively, if the correct size of brass ball is freely available in the USA, what's the problem? Fedex is your friend! (other couriers are available....).

As a matter of interest, why does a vacuum system need drip valves? Won't any water vapour would be removed along with the air?

 

The reason for a drip valve in the Vacuum Brake pipework is to drain condensation that develops when the system is not in use. They are attached at the low point(s) in the system. All air has moisture content - when the pipework is cooler than the air that was admitted into the system when the brake was last applied will condense. OK we are not talking about a bucket load of water, but water equals a corrosion potential and rust which has the potential to build up in critical areas....
The ORR has an oversight on all motive power new builds, Main Line or Heritage - mostly no problem - but IF... then you need that Technical Construction File. Of course, if you are going Main line you pay a shed load of cash to a third party (VAB) that reviews everything and issues a bit of paper... 567 is not going Main Line - Heritage use only - hence NO VAB charges, therefore a lower build cost.
Steve, thank you for pointing me in the direction of South Coast Steam of Portland - Barry Gambles tells me they offer the BR Design Drip Trap - so the National Preservation grape-vine works again.

 

NP triumphs again!....but I was going to suggest that somebody going to the US could bring a packet of balls back....

 

I can show you several railways and locos that use rubber balls. I can even show you the kids shop to buy them from....

I don't want to sound rude, but there is an awful lot more loco to build before this becomes an issue.

 

Phil, we already got someone to bring back the Boiler Blowdown valve in his luggage! Southern Steam do the complete assembly - just screw into the pipework. We do try to do things in-house, but a serious shortage of volunteers with skills is an issue to any project like this.
As for it not being an issue at this time 43729 - we do not have the luxury of having off the shelf drawings to work too - just the one G.A. What does that mean/ It means someone has to plan ahead and design how everything goes together, (see previous post re-engineers save projects money by designing). We need to know where to source the material, locate suitable sub-contractors where we don't have the ability to create the part - that has been my job since 2013 - so drip traps will be screwed in in several years time, but I will buy them and store them so we have them in stock for when somebody points to a hole in the pipework and asks what goes there - THINK AHEA^d

 

In my view my good friend Steve is spot on in his analysis. New vacuum brake pipe system condensate drain valves are readily available and those I use (seen here pictured sat in front of a drivers vacuum brake valve) not particular expensive and this version are available from Martyn Ashworth. And, if anyone does feel a pressing need for a risk assessment I suggest that would say. Risk = Drain valve leeks. Out-turn = Loss of vacuum so the brakes come on! Much the same fail safe nuisance type of out-turn as if such as a split appears in a rubber train pipe vacuum hose. In any event these drain valves work very well and in my experience dont tend to leak! Mike

 

Risk assessment comments noted - but nobody likes a train stopped in section full of passengers.... Mike, those Drain Traps by Martyn Ashworth are a good example of functional design - what do they cost and what is the mounting thread? Thanks for taking the time to send the pic.

 

Barry: Martyn Ashworth's company Heritage Transport Supplies Ltd advertises each month in the 'Traction and Rolling Stock Advertiser' so perhaps drop him a line- contact detail in those advertisements. That at http://www.tractionads.co.uk/?fbclid=IwAR0RFyF8g7334Qhpyy73KslsbmO66DjyqxrYVcCiHR77Uwe2KFx73F7cDlc

 

Thanks for the info Mike, I have sent Martyn an email

 

The various fittings supplied by Martyn were made by Charles Adams who unfortunately passed away this year. These will continue to be available but things are still tied up with probate at the moment. If you are not in a rush, all is well.

 

Steve, unfortunately age catches up with everyone.... A real problem in the case of those with skills, as we don't seem to have youngsters who can work on things that are not electronic. I don't think I will see 567 running in my lifetime - that's not because the rate of progress is somewhat slow (lack of volunteers with skills or even want to learn) - but at 72 I am already older than my dad and cousins were.... However we are not in a rush for these bits - its just a case of sorting what is available and buying it as and when.....

 

Very sensible to steadily acquire bits in advance.....You have a couple of years on me Legrandanglais......but I hope to see 567 steam across the "Gap", with Boscastle on the Windcutters and Brocklebank on the dining train following behind!